Christiaan Huygens, Lord of Zeelhem, was a Dutch mathematician, physicist, engineer, astronomer, and inventor who is regarded as a key figure in the Scientific Revolution.
120 Facts About Christiaan Huygens
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In physics, Huygens made seminal contributions to optics and mechanics, while as an astronomer he studied the rings of Saturn and discovered its largest moon, Titan.
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Christiaan Huygens first identified the correct laws of elastic collision in his work De Motu Corporum ex Percussione, completed in 1656 but published posthumously in 1703.
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In 1659, Christiaan Huygens derived geometrically the formula in classical mechanics for the centrifugal force in his work De vi Centrifuga, a decade before Newton.
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Christiaan Huygens invented the pendulum clock in 1657, which he patented the same year.
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In 1655, Christiaan Huygens began grinding lenses with his brother Constantijn to build refracting telescopes.
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Constantijn Christiaan Huygens was a diplomat and advisor to the House of Orange, in addition to being a poet and a musician.
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Christiaan Huygens corresponded widely with intellectuals across Europe; his friends included Galileo Galilei, Marin Mersenne, and Rene Descartes.
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Christiaan Huygens was educated at home until the age of sixteen, and from a young age liked to play with miniatures of mills and other machines.
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Constantijn Christiaan Huygens was closely involved in the new College, which lasted only to 1669; the rector was Andre Rivet.
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Christiaan Huygens lived at the home of the jurist Johann Henryk Dauber while attending college, and had mathematics classes with the English lecturer John Pell.
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Some of Mersenne's concerns at the time, such as the cycloid, the centre of oscillation, and the gravitational constant, were matters Christiaan Huygens only took seriously towards the end of the 17th century.
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Christiaan Huygens preferred meantone temperament; he innovated in 31 equal temperament, using logarithms to investigate it further and show its close relation to the meantone system.
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In 1654, Christiaan Huygens returned to his father's house in The Hague, and was able to devote himself entirely to research.
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Subsequently, Christiaan Huygens developed a broad range of correspondents, though picking up the threads after 1648 was hampered by the five-year Fronde in France.
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Besides, Christiaan Huygens was looking by then to apply mathematics to physics, while Fermat's concerns ran to purer topics.
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Between 1651 and 1657, Christiaan Huygens published a number of works that showed his talent for mathematics and his mastery of classical and analytical geometry, increasing his reach and reputation among mathematicians.
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Around the same time, Christiaan Huygens began to question Descartes's laws of collision, which were largely wrong, deriving the correct laws algebraically and later by way of geometry.
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Christiaan Huygens showed that, for any system of bodies, the centre of gravity of the system remains the same in velocity and direction, which Huygens called the conservation of "quantity of movement".
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Christiaan Huygens passed to Hevelius a manuscript of Jeremiah Horrocks on the transit of Venus in 1639, printed for the first time in 1662.
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Christiaan Huygens eventually created the first graph of a continuous distribution function under the assumption of a uniform death rate, and used it to solve problems in joint annuities.
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Contemporaneously, Christiaan Huygens, who played the harpsichord, took an interest in Simon Stevin's theories on music; however, he showed very little concern to publish his theories on consonance, some of which were lost for centuries.
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Christiaan Huygens took part in its debates, and supported its "dissident" faction favouring experimental demonstration over amateurish attitudes.
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Also in Paris, Christiaan Huygens made further astronomical observations using the observatory recently completed in 1672.
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Christiaan Huygens introduced Nicolaas Hartsoeker to French scientists such as Nicolas Malebranche and Giovanni Cassini in 1678.
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Christiaan Huygens met the young diplomat Leibniz while visiting Paris in 1672 on a vain mission to meet the French Foreign Minister Arnauld de Pomponne.
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An extensive correspondence ensued over the years, in which Christiaan Huygens showed at first reluctance to accept the advantages of Leibniz's infinitesimal calculus.
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Christiaan Huygens moved back to The Hague in 1681 after suffering another bout of serious depressive illness.
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Christiaan Huygens attempted to return to France in 1685 but the revocation of the Edict of Nantes precluded this move.
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Christiaan Huygens's father died in 1687, and he inherited Hofwijck, which he made his home the following year.
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Christiaan Huygens returned to mathematical topics in his last years and observed the acoustical phenomenon now known as flanging in 1693.
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Christiaan Huygens first became internationally known for his work in mathematics, publishing a number of important results that drew the attention of many European geometers.
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Christiaan Huygens's preferred method in his published works was that of Archimedes, though he used Descartes's analytic geometry and Fermat's infinitesimal techniques more extensively in his private notebooks.
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Christiaan Huygens demonstrated that the centre of gravity of a segment of any hyperbola, ellipse, or circle was directly related to the area of that segment.
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Christiaan Huygens was then able to show the relationships between triangles inscribed in conic sections and the centre of gravity for those sections.
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Quadrature was a live issue in the 1650s and, through Mylon, Christiaan Huygens intervened in the discussion of the mathematics of Thomas Hobbes.
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Christiaan Huygens showed that, in the case of the hyperbola, the same approximation with parabolic segments produces a quick and simple method to calculate logarithms.
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Christiaan Huygens appended a collection of solutions to classical problems at the end of the work under the title Illustrium Quorundam Problematum Constructiones.
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Christiaan Huygens became interested in games of chance after he visited Paris in 1655 and encountered the work of Fermat, Blaise Pascal and Girard Desargues years earlier.
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Christiaan Huygens eventually published what was, at the time, the most coherent presentation of a mathematical approach to games of chance in De Ratiociniis in Ludo Aleae.
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Christiaan Huygens included five challenging problems at the end of the book that became the standard test for anyone wishing to display their mathematical skill in games of chance for the next sixty years.
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Christiaan Huygens had earlier completed a manuscript in the manner of Archimedes's On Floating Bodies entitled De Iis quae Liquido Supernatant.
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Christiaan Huygens then proves the general theorem that, for a floating body in equilibrium, the distance between its centre of gravity and its submerged portion its at a minimum.
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Christiaan Huygens uses this theorem to arrive at original solutions for the stability of floating cones, parallelepipeds, and cylinders, in some cases through a full cycle of rotation.
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Christiaan Huygens's approach was thus equivalent to the principle of virtual work.
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Christiaan Huygens was the first to recognize that, for these homogeneous solids, their specific weight and their aspect ratio are the essentials parameters of hydrostatic stability.
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Christiaan Huygens was the leading European natural philosopher between Descartes and Newton.
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However, unlike many of his contemporaries, Christiaan Huygens had no taste for grand theoretical or philosophical systems and generally avoided dealing with metaphysical issues.
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In common with Robert Boyle and Jacques Rohault, Christiaan Huygens advocated an experimentally oriented, corpuscular-mechanical natural philosophy during his Paris years.
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Newton's influence on John Locke was mediated by Christiaan Huygens, who assured Locke that Newton's mathematics was sound, leading to Locke's acceptance of a corpuscular-mechanical physics.
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Christiaan Huygens studied elastic collisions in the 1650s but delayed publication for over a decade.
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Christiaan Huygens concluded quite early that Descartes's laws for the elastic collision of two bodies must be wrong, and he formulated the correct laws, including the conservation of the product of mass times the square of the speed for hard bodies, and the conservation of quantity of motion in one direction for all bodies.
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Christiaan Huygens had worked out the laws of collision from 1652 to 1656 in a manuscript entitled De Motu Corporum ex Percussione, though his results took many years to be circulated.
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The war ended in 1667, and Christiaan Huygens announced his results to the Royal Society in 1668.
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Christiaan Huygens later published them in the Journal des Scavans in 1669.
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In 1659 Christiaan Huygens found the constant of gravitational acceleration and stated what is known as the second of Newton's laws of motion in quadratic form.
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Christiaan Huygens derived geometrically the now standard formula for the centrifugal force, exerted on an object when viewed in a rotating frame of reference, for instance when driving around a curve.
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Christiaan Huygens collected his results in a treatise under the title De vi Centrifuga, unpublished until 1703, where the kinematics of free fall were used to produce the first generalized conception of force prior to Newton.
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Yet, the interpretation of Newton's work on gravitation by Christiaan Huygens differed from that of Newtonians such as Roger Cotes: he did not insist on the a priori attitude of Descartes, but neither would he accept aspects of gravitational attractions that were not attributable in principle to contact between particles.
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The approach used by Christiaan Huygens missed some central notions of mathematical physics, which were not lost on others.
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In 1657, inspired by earlier research into pendulums as regulating mechanisms, Christiaan Huygens invented the pendulum clock, which was a breakthrough in timekeeping and became the most accurate timekeeper for almost 300 years until the 1930s.
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Christiaan Huygens contracted the construction of his clock designs to Salomon Coster in The Hague, who built the clock.
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However, Christiaan Huygens did not make much money from his invention.
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In 1660, Lodewijk Christiaan Huygens made a trial on a voyage to Spain, and reported that heavy weather made the clock useless.
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Alexander Bruce elbowed into the field in 1662, and Christiaan Huygens called in Sir Robert Moray and the Royal Society to mediate and preserve some of his rights.
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Sixteen years after the invention of the pendulum clock, in 1673, Christiaan Huygens published his major work on horology entitled Horologium Oscillatorium: Sive de Motu Pendulorum ad Horologia Aptato Demonstrationes Geometricae.
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Christiaan Huygens's motivation came from the observation, made by Mersenne and others, that pendulums are not quite isochronous: their period depends on their width of swing, with wide swings taking slightly longer than narrow swings.
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Christiaan Huygens tackled this problem by finding the curve down which a mass will slide under the influence of gravity in the same amount of time, regardless of its starting point; the so-called tautochrone problem.
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The mathematics necessary to solve this problem led Christiaan Huygens to develop his theory of evolutes, which he presented in Part III of his Horologium Oscillatorium.
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Christiaan Huygens solved a problem posed by Mersenne earlier: how to calculate the period of a pendulum made of an arbitrarily-shaped swinging rigid body.
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Christiaan Huygens was the first to derive the formula for the period of an ideal mathematical pendulum, in modern notation:.
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Christiaan Huygens observed coupled oscillations: two of his pendulum clocks mounted next to each other on the same support often became synchronized, swinging in opposite directions.
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Christiaan Huygens reported the results by letter to the Royal Society, and it is referred to as "an odd kind of sympathy" in the Society's minutes.
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In 1675, while investigating the oscillating properties of the cycloid, Christiaan Huygens was able to transform a cycloidal pendulum into a vibrating spring through a combination of geometry and higher mathematics.
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The implication is that Christiaan Huygens thought his spiral spring would isochronize the balance in the same way that cycloid-shaped suspension curbs on his clocks would isochronize the pendulum.
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Christiaan Huygens later used spiral springs in more conventional watches, made for him by Thuret in Paris.
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Watches in Christiaan Huygens's time employed the very ineffective verge escapement, which interfered with the isochronal properties of any form of balance spring, spiral or otherwise.
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Christiaan Huygens's design came around the same time as, though independently of, Robert Hooke's.
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Christiaan Huygens had a long-term interest in the study of light refraction and lenses or dioptrics.
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Christiaan Huygens was one of the few to raise theoretical questions regarding the properties and working of the telescope, and almost the only one to direct his mathematical proficiency towards the actual instruments used in astronomy.
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Christiaan Huygens repeatedly announced its publication to his colleagues but ultimately postponed it in favor of a much more comprehensive treatment, now under the name of the Dioptrica.
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In contrast to Descartes' dioptrics which treated only ideal lenses, Christiaan Huygens dealt exclusively with spherical lenses, which were the only kind that could really be made and incorporated in devices such as microscopes and telescopes.
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Christiaan Huygens worked out practical ways to minimize the effects of spherical and chromatic aberration, such as long focal distances for the objective of a telescope, internal stops to reduce the aperture, and a new kind of ocular known as the Huygenian eyepiece.
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Together with his brother Constantijn, Christiaan Huygens began grinding his own lenses in 1655 in an effort to improve telescopes.
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Christiaan Huygens designed in 1662 what is called the Huygenian eyepiece, a set of two planoconvex lenses used as a telescope ocular.
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Christiaan Huygens's lenses were known to be of superb quality and polished consistently according to his specifications; however, his telescopes did not produce very sharp images, leading some to speculate that he might have suffered from near-sightedness.
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Lenses were a common interest through which Christiaan Huygens could meet socially in the 1660s with Spinoza, who ground them professionally.
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Christiaan Huygens encountered the work of Antoni van Leeuwenhoek, another lens grinder, in the field of microscopy which interested his father.
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Christiaan Huygens is credited as the inventor of the magic lantern, described in correspondence of 1659.
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Christiaan Huygens is especially remembered in optics for his wave theory of light, which he first communicated in 1678 to the Academie des sciences in Paris.
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Christiaan Huygens refers to Ignace-Gaston Pardies, whose manuscript on optics helped him on his wave theory.
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Christiaan Huygens had experimented in 1672 with double refraction in the Iceland spar, a phenomenon discovered in 1669 by Rasmus Bartholin.
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Christiaan Huygens's theory posits light as radiating wavefronts, with the common notion of light rays depicting propagation normal to those wavefronts.
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One strong objection to Christiaan Huygens's theory was that longitudinal waves have only a single polarization which cannot explain the observed birefringence.
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In 1655, Christiaan Huygens discovered the first of Saturn's moons, Titan, and observed and sketched the Orion Nebula using a refracting telescope with a 43x magnification of his own design.
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Christiaan Huygens succeeded in subdividing the nebula into different stars, and discovered several interstellar nebulae and some double stars.
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Much more than a report on Saturn, Christiaan Huygens provided measurements for the relative distances of the planets from the Sun, introduced the concept of the micrometer, and showed a method to measure angular diameters of planets, which finally allowed the telescope to be used as an instrument to measure astronomical objects.
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Christiaan Huygens was the first to question the authority of Galileo in telescopic matters, a sentiment that was to be common in the years following its publication.
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At the instigation of Jean-Baptiste Colbert, Christiaan Huygens undertook the task of constructing a mechanical planetarium that could display all the planets and their moons then known circling around the Sun.
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Christiaan Huygens completed his design in 1680 and had his clockmaker Johannes van Ceulen built it the following year.
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However, Colbert passed away in the interim and Christiaan Huygens never got to deliver his planetarium to the French Academy of Sciences as the new minister, Francois-Michel le Tellier, decided not to renew Christiaan Huygens's contract.
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Shortly before his death in 1695, Christiaan Huygens completed his most speculative work entitled Cosmotheoros.
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Such speculations were not uncommon at the time, justified by Copernicanism or the plenitude principle, but Christiaan Huygens went into greater detail.
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Christiaan Huygens's work was fundamentally utopian and owes some inspiration from the cosmography and planetary speculation of Peter Heylin.
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Christiaan Huygens wrote that availability of water in liquid form was essential for life and that the properties of water must vary from planet to planet to suit the temperature range.
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Christiaan Huygens took his observations of dark and bright spots on the surfaces of Mars and Jupiter to be evidence of water and ice on those planets.
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Christiaan Huygens argued that extraterrestrial life is neither confirmed nor denied by the Bible, and questioned why God would create the other planets if they were not to serve a greater purpose than that of being admired from Earth.
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Christiaan Huygens postulated that the great distance between the planets signified that God had not intended for beings on one to know about the beings on the others, and had not foreseen how much humans would advance in scientific knowledge.
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Christiaan Huygens made a series of smaller holes in a screen facing the Sun, until he estimated the light was of the same intensity as that of the star Sirius.
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Christiaan Huygens has been called the first theoretical physicist and a founder of modern mathematical physics.
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Christiaan Huygens helped develop the institutional frameworks for scientific research on the European continent, making him a leading actor in the establishment of modern science.
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In mathematics, Christiaan Huygens mastered the methods of ancient Greek geometry, particularly the work of Archimedes, and was an adept user of the analytic geometry and infinitesimal techniques of Descartes, Fermat, and others.
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Christiaan Huygens brought this type of geometrical analysis to a close, as more mathematicians turned away from classical geometry to the calculus for handling infinitesimals, limit processes, and motion.
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Christiaan Huygens was moreover able to fully employ mathematics to answer questions of physics.
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Christiaan Huygens favoured axiomatic presentations of his results, which require rigorous methods of geometric demonstration: although he allowed levels of uncertainty in the selection of primary axioms and hypotheses, the proofs of theorems derived from these could never be in doubt.
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Besides the application of mathematics to physics and physics to mathematics, Christiaan Huygens relied on mathematics as methodology, particularly its ability to generate new knowledge about the world.
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Unlike Galileo, who used mathematics primarily as rhetoric or synthesis, Christiaan Huygens consistently employed mathematics as a method of discovery and analysis, and insisted that the reduction of the physical to the geometrical satisfy exacting standards of fit between the real and the ideal.
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Christiaan Huygens came close to the modern idea of limit while working on his Dioptrica, though he never used the notion outside geometrical optics.
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Christiaan Huygens's standing as the greatest scientist in Europe was eclipsed by Newton's at the end of the seventeenth century, despite the fact that, as Hugh Aldersey-Williams notes, "Christiaan Huygens's achievement exceeds that of Newton in some important respects".
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Additionally, Christiaan Huygens developed the oscillating timekeeping mechanisms, the pendulum and the balance spring, that have been used ever since in mechanical watches and clocks.